Abstract: A primer is disclosed for installation in a floor drain water trap located in a lower position relative to a sink drain and sink water trap. A first fitting is disposed upstream of the floor drain water trap. A second fitting is disposed in the sink drain upstream of the sink water trap. A conduit interconnects the first and second fittings to direct waste water from the sink drain to the floor drain water trap thereby maintaining the water level therein to insure a proper seal in the floor drain water trap. The foregoing abstract is merely a resume of one general application, is not a complete discussion of all principles of operation or applications, and is not to be construed as a limitation on the scope of the claimed subject matter.